Pump for type-casting machines.



F.' H. PIRPGNT. PUMP Fos TYPE CASTING MACHINES.

APPLICATION FILED .IUNE I2. 1,912.

' Patented Aug. 10, 1915.

3 SHEETS-SHEET I.

Mull/l Patented Aug. 10, 1915.

3 SHEETS-SHEET 2.

F.`H. PIERPONT. P'UMP FOR TYPE CASTING MACHINES. APPLICATION FILED JUNE I2. 19I2 1,149,285.

Y i SK F; 'Hl PIERPONT.` PUMP FOP TYPE CASTING MACHINES.' APPucQATloN FILED June 12. 1.912,.

1,149,285. Patented Aug. 10, 1915.

a sHETssHEsT 3.

cruzan sfmEEs PAEENT oEEicE.

FRANK'HINMAN PIERPONT, OF HORLEY, ENGLAND, ASSIGNOR T0 LANSTON MONOTYP MACHINE COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION 0F VIRGINIA.

i PUMP FOB. TYPE-CASTING MACHINES.

v specification of Letters Patent. l PatentetAug. 10, 1915.

Application led J une 12, 1912. Serial'No. 703,264v

Surrey, England, haveinvented a certain new and useful Improvement in or Relating to Pumps for Type-Casting Machines; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had tothe accompanying drawings, forming a part of this specicnl tion, and to the figures and letters of refer?y ence marked thereon.

This invention relates to pumps for type casting machines, such as are described in the specification of British Letters Patent Ngs. 8038/09 and 8980/01 (U. S. Patents ce nos of May 3o, ieee and 674,374 of May 21, 1901). These pumps are operated at a comparatively high rate Of speed to deliver metal to a mold, the capacity of which is varied from time to time for the different type bodies cast and great ditiiculty'exists in preventing the pump from acting irregularly or iini'noperly due either to the fouling of the nozzle or, where there is a drawback of `the metal to prevent fouling, to the solidifying of some of the metal in the' nozzle due to chilling. lf there is ,too great a drawback of metal from the nozzle further difficulty arises in getting rid of the air in the nozzle which otherwise enters the mold and prevents tbe production of solid types. Various attempts have been made, with more or less satisfactory results, to overcome these drawbacks, for example, in the specification of British Letters Patent No. 4201/09, (U. S. Patent 720,714, datedFeb. 17, 1903) afvalve is placed between the pump piston and the channel leading to the nozzle to prevent too great a drawback of fluid from the nozzle and avoid chilling and the collection of a large body of air, and in order to allow1 a small drawback and prevent fouling of the nozzle, a by-pass is formed through or` around the valve to connect the inlet and outlet channels or passages. This valve is separated from the nozzle by a considerable length of channel in which there is always, a

large body of metal, and has not got a c'oihplete control of the metal in the nozzle.

According to the present invention, there i y l il. inl

is placed in the delivery nozzle near to the outlet or tip thereof or between the nozzle and the channel leading from the cylinder, a

to be raised from its seat by the metal on each ejection stroke and floats back to its seat on the return stroke of the piston so as to trap some metal in the nozzle itself. or prevent a large drawback of metal, allowing only a suiiicient drawback to avoid fouling,

and to insure that this valve operates propA erly, there is provided a kicker, actuated at each delivery stroke of the pump, to unseat or insure the unseating of the valve should it stick. Further, in order to prevent or minimize the likelihood' of a second shot ori., double delivery, the nozzle is formed with an i obstructed or tortuous passage.

The invention will be described as applied tothe pump forming the subject matter of British Lettersv Patent No. 8980/01 (U. S. Patent 674,374) to the specification of which reference may be had 'for a detailed description of the construction of and of the operating mechanism of the pump.

.Referring to the accompanying drawings: Figure 1 is a sectional elevation of the pump body. Fig. 1? is a. sectional elevation of the nozzle on a larger scale than that of F ig. 1.l

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Fig. Q is a plan of Fig. 1. Fig. 3 is a section on thel line 3 3, of Fig. 2. Fig. e is a sectional elevation showing the pump operating mechanism. l l1 Ads the non-return valve in the nozzle.

Bf'is the lever or kickerforidisplacing the valve, and C is a plug in the njzzlel It is not deemed necessafryi to give a detailed description of the partis of the pump with which the present; in nt on is not directly concerned as theselaiefully set forth in the speeificationalreadiv referredv to, a

brief description of theiparts suflieient for a clear 'understandirg of the present invention, however, will be given.

The pum cylinder D is set in and is mov- 'able relatiifely to ithe meltingpot E under the actiin t f the lewers F and a spring F2 by whi'h libe punp is lifted to engage the tihereof ith ,theinold 5 nozzle i G isltheg pnmppiston which id ,reciprocated bj levers H H connected'together by a llnk i ope end Vof the lever Hl being in 55 ball or other non-return valve which is free engagement with the pump body and the corresponding end of the lever H' with the pump plunger or piston. A driving shaft H2 is connected by an arln H3 to a rod HJx 5 pivotally connected to thev free enl of the lever H and between the arln Haan( acollar on the rod H4 is a spring H5. v

Hs is a vertical shaft carrying a head HT extending beneath ,the-arm H3 and connected to the free end of the lever H.

The spring H5 normally tends to elevate rod H4 and a spring H tends to hold the parts H3 and H7 in contact while the shaft raises the pump to the mold, vafter which further movement of lthe shaft vacting through spring H5 transmits motion to'lever v H to give stroke to the piston.

vThe metal in which the pumpcylinder D is immersed enters the cylinder when the 2o piston G'i's at the upper. end of its stroke,

through the inlet opening el in the cylinder` and a cavity g in the piston. The cavity g communicates with an annular cavity g on the outer periphery of the piston, by a convenient number of passages g2 which register with the inlet opening d when the piston is at the upper end of its travel.

K is a valve by which the flow of metal through theinlet opening is controlled. The

pump cylinder communicates below the pis,

ton with the nozzle D by a channel D2.

According to this invention, a non-return valve A, preferably of ball type, 'is placed in a small chamber @situated in the nozzle V and seats inwardly on a seating a formed in the chamber'.

\the pump cylinder on the delivery side of the piston, to the nozzle. The pump is raised as hitherto to bring the nozzle into 40 contact witha seat on the mold by the mechanism referred to and after the nozzle is se ted the pump piston is actuated. As the pidton descends it forces the metal in the cylinder albng the channel D2 and through the nozzle D. After 'the metal is injected into the ,mold, the piston performs its return stroke and the valve A floats down onto its seat as thev metal recedes, allowing a suliicient drawback of metal to 'avoid fouling when the nozzle is lowered from the mold seat, but preventing an objectionable body of air entering Athe nozzle and channel.

In order' to'dinsure that the valve A will be dislodgedfor nnseated at each delivery stroke, a kicker B is provided to act on the valve on vor during each delivery stroke of the piston. Preferably this kicker is operated positively by the piston and is in the form of a lever B located in the channel I)2 and pivoted at d to theA walls thereof. ()ne end of the lever is connected to a rod B which passes up the bore of the nozzle and terminates a little distance below the valve. The thickness of the rod is such as not The channel AD2 leads fromobstruct the flow 'ofJ-he metal through the nozzle. The other end of the lever B projects below the pump piston inthe Apath of a boss G2 thereon and before the, piston reaches the lower end of its stroke it acts upon this end of the lever B forcing its other end up against the valve to unseat it should it not have acted.

The plug C in the nozzle prevents the valve A from closing the outlet passage in the nozzle, and the passages C formed vbetween the walls of the plug and the inner walls of the bore in the nozzle are tortuous i passages which break up the How and tend to prevent a double discharge. y

L is a cylindrical liner placed between the piston and the pump cylinder walls to pro- .nozzle and the channel leading to the pump cylinder, of a plug which acts as a stop for the valve there being a passagel for the meta-l to pass the plug, substantially as described.

2. In a molten metal injecting mechanism for type casting machines, the combination with a pump, a discharge passa/ge and a nozzle, of an inwardly seating non-return valve located within the nozzle and operating to retain thelnolten metal within the discharge passage adjacent said nozzle and to permitl of a limited drawback of the metal in the exit opening.

3. In a molten metal injecting mechanism for type casting machines, the combination with a pump and a discharge-passage communicating therewith and terminating in a nozzle, of a floating inwardly seating nonreturn valve located withiny the nozzle and controlling the opening of the discharge passage, and a kicker operated during the operative part of each discharge-stroke of the pump piston, to unseat the non-return valve. l

4. In a molten metal injecting mechanism Y,

for type casting machines provided with a pump and a discharge passage terminating in a nozzle having an internal chamber, and in combination therewith :u non-return valve, located within the chamber in the nozzle and controlling the opening from the discharge passage therein, and a plug partially closing the disclnirge end of said ychamber andA acting as a stop for said nonreturn valve. 5. In amolten metal injecting mechanism for type Vcasting machines equipped with a lpump, a dschage passage there-from, and upon the non-returnv valve to unseat thel a. nozzle applied to the discharge 1nd of laid latter. 4

passage and in combination t erewit a f non-retlirn valve controlling the discharge FRANK HINMAN PIERPONT" 5 end'of said passage, and a kicker engaged /Vitnesses:

Vby the piston at the beginning of the opera- W.l L. BURCH,

tive, disha-rgng'stroke thereof and acting WiL-.l DOW. 

